The thalamus is both a major relay station of sensory and perceptual information to the cortex as well as an important reciprocal participant in cortical action. These roles, both relevant to the sensory processing and executive action deficits in schizophrenia, make the thalamus a leading candidate structure for the defective link in the neural circuits involved in the disease diathesis. We begin with an existing sample of high resolution MR (1.2 mm spacing, SPGR) images of 76 normal controls (ages 20-90; 5 men, 5 women in each decade with oversampling of the 20-30 year group) and 42 unmedicated schizophrenic patients (including 10 never-medicated). We will add an additional older cohort of 32 patients to match the age and clinical course of an autopsy sample currently under study in another project and a younger cohort (n=24) of not previously medicated schizophrenic adolescents (age 13-18) and young adults (age 18-29). Lastly we will add 24 normal adolescents. This will yield a final population of 100 normals and 100 patients. We will examine 1) MRI anatomy of the major nuclear groups of the thalamus in a 100-person normal lifespan cohort and 100 patients with schizophrenia (ages 13-75); 2) white matter connections of the thalamus using diffusion tensor imaging to visualize direction and alignment of axon bundles and MRI morphometry to assess the internal capsule; and 3) volume of the gray and white matter of regions of the cortex reciprocally linked to the medial dorsal nucleus (prefrontal, cingulate, temporal regions). The medial dorsal and anterior regions are more closely connected with the frontal lobe and cingulate gyrus, while the pulvinar is more closely associated with temporal and occipital cortex. The data collected will illuminate relationships between volume loss in specific nuclei of the thalamus and cortical areas associated with these thalamic nuclei. The project brings the resources and the imaging/anatomical researchers of the Mount Sinai Department of Psychiatry, Neuroscience PET laboratory and the Department of Radiology together into a multidisciplinary and multimodal imaging consortium.